开发区内各功能区除满足相互间的影响最小，并留有充足的空间防护距离外，还应从基础设施建

根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。（请把答案抄写在答题区）

Although many Chinese students say that their knowledge of English grammar is good, most would admit that their spoken English is poor. Whenever I speak to a Chinese student, they always say, “My spoken English is poor.”   1   I would like to suggest that there may be some reasons for their problems with spoken English.

First, they fail to find suitable words to express themselves due to a limited vocabulary.  2   However, you can speak with a limited vocabulary, if you choose a positive attitude. Others will follow you as long as you use the words that you know.

3   Sometimes they make mistakes when they are speaking because they are shy and nervous. Yet students should remember that their goal should be FLUENCY NOT ACCURACY. Your aim in writing is to be accurate following the rules for grammar and using the right words and spelling them correctly. However, in speaking your aim is fluency. You want to get your message across, to talk to someone in English, as quickly and as well as you can, even though sometimes you may use a wrong word or tense, but it doesn't matter.    4  

The third reason is that not enough attention is paid to listening. You have one mouth but two ears! All that hearing is necessary for you to start speaking.

Fourth, most Chinese students are reactive rather than proactive language learners. Instead of actively seeking out opportunities to improve their spoken English, they passively wait for speaking opportunities to come to them and wonder why their English always remains poor.    5  

A．The person you are speaking to will understand you and make allowances for any mistakes he hears.

B．They may try to avoid making similar mistakes next time.

C．Obviously the better answer is to expand their vocabulary.

D．If you have this proactive outlook, then you will see English opportunities wherever you go.E. However, their spoken English does not have to remain “poor”！

F. Second, they are afraid of making mistakes.

G. The second reason lies in the reluctance of using what has just been learned.

“神州六飞船”是由我国自行研制的长征火箭发射升空的．当火箭在太空中高速飞行时，它的头部与空气摩擦，温度可升至几千摄氏度，为了防止烧坏火箭内部搭载的仪器和设备，常在火箭的头部涂有一层特殊的材料，为什么？

工业上制氯化铜无水物时，是将浓盐酸用蒸气加热至80 ℃左右，慢慢加入粗制氧化铜粉(含杂质氧化亚铁和SiO₂)，充分搅拌后使之溶解，制取流程如下：

已知：pH≥9.6时，Fe²⁺以Fe(OH)₂的形式完全沉淀；pH≥6.4时，Cu²⁺以Cu(OH)₂的形式完全沉淀；常温时K_sp[Fe(OH)₃]=c(Fe³⁺).c³(OH^－)=1.0×10^－38。试回答：

(1)根据常温时Fe(OH)₃的K_sp计算，当溶液中的Fe³⁺完全沉淀(此时溶液中的Fe³⁺物质的量的浓度=10^－5mol/L)，溶液的pH=             。

(2)溶液D制取无水CuCl₂时，需在HCl气体中蒸干，原因是                      

                                                                        。

(3)粗CuO溶于过量盐酸后，得到的溶液B中加入试剂x将Fe²⁺氧化为Fe³⁺，试剂x可以是          (填以下选项序号)。

A．KMnO₄溶液    B．氯水    C．NaClO溶液    D．O₃

若用H₂O₂溶液，则反应的离子方程式为                                   。

(4)溶液C加入试剂y，要调整溶液的pH至3-4，试剂y不能是       (填以下选项序号)，原因是                                                              。

A．NaOH溶液    B．Cu(OH)₂固体    C．Cu₂(OH)₂CO₃固体    D．CuO固体

(5)将ag粗CuO经过以上一系列操作之后，最终得到bg无水CuCl₂(不考虑实验过程中操作引起的损耗)，下列说法正确的是          。(N_A表示阿伏伽德罗常数)

A．粗CuO中Cu²⁺数目小于         

B．粗CuO中CuO物质的量小于mol

C．粗CuO中所含的铜元素的质量分数为×100℅ 

D．粗CuO中关于CuO的量无法确定

慢性肾炎并尿毒症时，血清尿素氮（BUN）和血浆二氧化碳结合力（CO2CP）检查结果（）

A.BUN升高，CO2CP升高

B.BUN降低，CO2CP升高

C.BUN正常，CO2CP升高

D.BUN升高，CO2CP降低

E.BUN正常，CO2CP正常

变频器是将（）频率的交流电变换为频率连续可调的交流电的装置。